SubX predicted rainfall events from Tropical Storm Isaias

SubX predicted rainfall events from Tropical Storm Isaias

Side by side comparison of SubX rainfall (left) and actual as recorded by the National Weather Service
By Diana Udel, Director of Communications, Rosenstiel School

Side by side comparison of SubX rainfall (left) and actual as recorded by the National Weather Service

SubX predicted rainfall events from Tropical Storm Isaias

By Diana Udel, Director of Communications, Rosenstiel School
The UM Rosenstiel School research project proves its capabilities in real-time predictions

The extreme rainfall that impacted  the Caribbean and U.S. East from Tropical Storm Isaias was captured by scientists working on the next frontier of weather forecasting. 

The Subseasonal Experiment, a research-to-operations project designed to provide 3-to-4 week forecasts to the National Weather Service, predicted heavy rainfall in the Caribbean and along the East Coast nearly four weeks in advance, before the system that would be Isaias had even formed. Sub-seasonal forecasts can provide emergency managers and cities more lead time to prepare for extreme weather events. 

“We always suspected the predictive capability was there to deliver sub-seasonal forecasts,” said Ben Kirtman, a professor of atmospheric sciences at the UM Rosenstiel School of Marine and Atmospheric Science and director of the NOAA Cooperative Institute for Marine and Atmospheric Studies (CIMAS). “This was evidence that we have the capability and need to study it further to get to an operational phase.”

Kirtman and colleagues have learned that SubX currently has more success predicting precipitation in the summer and predicting temperature in the winter. As SubX becomes more reliable, scientists are increasingly confident that climatic forcing is making extreme rainfall more predictable.

SubX also predicted the heavy precipitation experienced during 2017’s Hurricane Harvey and  2018’s Hurricane Michael weeks in advance, and the extreme cold from the January–February 2019 “Polar Vortex”. 

Read more about weather forecasting science at the Rosenstiel School